Convert string to number that ends with newline

• trim

fn main() {
    let text = "23\n";
    println!("'{}'", text);
    let number: i32 = text.parse().expect("Could not convert to i32");

    println!("'{}'", number);
    println!("'{}'", number + 1);
}

'23
'
thread 'main' panicked at 'Could not convert to i32: ParseIntError { kind: InvalidDigit }', string_to_int_fail.rs:6:10
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace